We have some on our system.
They are classed to H6 so they are good for transmission weights and use.
we also have rust coated poles and galvanized poles, they all are holding up well.
As far as whipping, the poles are guyed so they aren’t like a light pole.
We have MANY fiberglass light poles (16-25’) in residential areas. Absolutely no problem.
I took some down that were installed some 25-30 years ago in a neighborhood.
the poles were in such good shape they are in my yard with lights on them now